The Claim
In older, mobility-limited women with vitamin D insufficiency, daily supplementation with 4000 IU of vitamin D₃ for 4 months increases total muscle fiber cross-sectional area by approximately 10% compared to a placebo control group, indicating a potential anabolic effect on skeletal muscle.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
For older women who have trouble moving around and don’t have enough vitamin D, taking a daily vitamin D pill for four months might make their muscle fibers about 10% bigger than if they took a sugar pill — which could mean it helps build muscle.
See the scientific wording
In older, mobility-limited women with vitamin D insufficiency, daily supplementation with 4000 IU of vitamin D₃ for 4 months increases total muscle fiber cross-sectional area by approximately 10% compared to placebo, indicating a potential anabolic effect on skeletal muscle.
What the research says
1 studyThis study gave older women with low vitamin D a daily pill of 4000 IU of vitamin D for 4 months and found their muscle fibers got about 10% bigger — just like the claim said.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.